1. Technical Field
The following description relates to one or more developer supply devices configured to supply charged powdered development agent to an intended device.
2. Related Art
A developer supply device has been known that includes a photoconductive drum, a development roller, and a developer electric-field transfer unit.
The development roller is disposed to face the photoconductive drum in a predetermined area. The development roller has a developer holding surface configured to hold and carry charged development agent thereon.
The developer electric-field transfer unit is disposed to face the developer holding surface across a predetermined distance at an upstream side relative to the development area in a moving direction of the developer holding surface (i.e., a moving direction of a circumferential surface of the development roller which surface moves in response to rotation of the development roller). The developer electric-field transfer unit includes a plurality of transfer electrodes. The developer electric-field transfer unit is configured to transfer the development agent by the action of a traveling-wave electric field generated when a transfer bias containing a multi-phase alternating-current (AC) voltage component is applied to the transfer electrodes.
In such a configuration, the development agent, transferred under the traveling-wave electric-field generated by the developer electric-field transfer unit, adheres onto the developer holding surface in a position where the developer electric-field transfer unit faces the development holding surface. Namely, in the position, the development agent is held and carried on the developer holding surface.
The development agent held on the developer holding surface is conveyed up to the development area with the developer holding surface moving in response to rotation of the development roller, and supplied for development of an electrostatic latent image. Thereby, the development agent adheres, in a shape of an image corresponding to the electrostatic latent image, onto an electrostatic latent image holding surface as a circumferential surface of the photoconductive drum. In other words, the electrostatic latent image on the electrostatic latent image holding surface is developed with the development agent. Thereby, an image of development agent (a developer image) is formed on the electrostatic latent image holding surface.